Suction stabilized epicardial ablation devices

ABSTRACT

A suction assisted ablation device having a support surface, suction elements disposed adjacent the support surface, at least one electrode and at least one suction conduit is provided. The device may further include fluid openings, which allow fluid to irrigate target tissue and aid in ablation. A method for ablating tissue using suction is also provided.

FIELD OF THE INVENTION

[0001] This invention relates to ablation devices that are used tocreate lesions in tissue. More particularly, this invention relates toablation devices that use vacuum or suction force to hold the tissue ina manner that creates linear lesions.

BACKGROUND OF THE INVENTION

[0002] The action of the heart is known to depend on electrical signalswithin the heart tissue. Occasionally, these electrical signals do notfunction properly. Ablation of cardiac conduction pathways in the regionof tissue where the signals are malfunctioning has been found toeliminate such faulty signals. Ablation is also used therapeuticallywith other organ tissue, such as the liver, prostate and uterus.Ablation may also be used in treatment of disorders such as tumors,cancers or undesirable growth.

[0003] Currently, electrophysiology (EP) ablation devices generally haveone or more electrodes at their tips. These devices may be used for bothdiagnosis and therapy. In one instance, electrodes at the tips of EPablation devices allow the physician to measure electrical signals alongthe surface of the heart. This is called mapping. When necessary, inanother instance, the physician can also ablate certain tissues using,typically, radio frequency (RF) energy conducted to one or more ablationelectrodes.

[0004] Sometimes ablation is necessary only at discrete positions alongthe tissue, is the case, for example, when ablating accessory pathways,such as in Wolff-Parkinson-White syndrome or AV nodal reentranttachycardias. At other times, however, ablation is desired along a line,called linear ablation. This is the case for atrial fibrillation, wherethe aim is to reduce the total mass of electrically connected atrialtissue below a threshold believed to be critical for sustaining multiplereentry wavelets. Linear lesions are created between electricallynon-conductive anatomic landmarks to reduce the contiguous atrial mass.

[0005] Linear ablation is currently accomplished in one of several ways.One way is to position the tip portion of the ablation device so that anablation electrode is located at one end of the target site. Then energyis applied to the electrode to ablate the tissue adjacent to theelectrode. The tip portion of the electrode is then slid along thetissue to a new position and then the ablation process is repeated. Thisis sometimes referred to as the burn-drag-burn technique. This techniqueis time-consuming (which is not good for the patient) and requiresmultiple accurate placements of the electrode (which may be difficultfor the physician). Furthermore, even if the ablation process creates acontinuously linear line along the top surface of the target tissue, itis not assured that the tissue is continuously and completely ablatedthrough further layers of the target tissue (i.e. it is not assured thattransmurality is achieved.)

[0006] A second way of accomplishing linear ablation is to use anablation device having a series of spaced-apart band or coil electrodeswhich, after the electrode portion of the ablation device has beenproperly positioned, are energized simultaneously or one at a time tocreate the desired lesion. If the electrodes are close enough togetherthe lesions run together sufficiently to create a continuous linearlesion. While this technique eliminates some of the problems associatedwith the burn-drag-burn technique, some repositioning of the ablationdevice may be required to create an adequately long lesion. In addition,it may be difficult to obtain adequate tissue contact pressure for eachelectrode in a multi-electrode ablation device. Also, the use ofmultiple electrodes to create the linear lesion tends to make the tipportion more expensive to make, more bulky and may cause the tip portionto be stiffer than with a single electrodes.

[0007] Another ablation-related problem results from the delivery of RFenergy to muscular tissue, such as the heart. Ablation of such tissueusing conventional ablation devices has a tendency to char or burn theblood or tissue with which the electrodes are in contact if thetemperatures exceed a certain threshold (for example, greater than 50°C.). This increases the difficulty of the ablation process because it isnecessary to clean the tip portion after a series of burns. Moreover,overheating the blood in the vicinity of the target site can desiccatethe blood and can cause overburning.

[0008] It would be desirable to have an ablation device which is easy toposition in relation to the target tissue and which stays stable inposition in relation to the target tissue.

[0009] It would further be desirable to have an ablation device which,when positioned, is capable of easily creating a linear, transmurallesion.

[0010] It would further be desirable to have an ablation device that isable to monitor tissue temperature in order to avoid burning the tissue.

SUMMARY OF THE INVENTION

[0011] One aspect of the present invention provides a suction assistedablation device. The device includes a support surface, having a firstand a second face, a plurality of suction elements disposed adjacent thesupport surface on the first face, at least one conductive elementdisposed adjacent the support surface on the first face, and at leastone suction conduit operatively connected with the suction elements. Thedevice may also include a maneuvering apparatus, such as a pull wireassembly. The device may also include at least one thermocouple element.The device may include one conductive element on a first support surfaceand a separate conductive element on a second support surface. Theconductive element may be a plurality of needle electrodes. The devicemay also include at least one fluid opening, which may be located withinthe conductive element. The conductive element may also be made of amaterial capable of releasing fluid.

[0012] Another aspect of the invention provides a method of ablatingtissue. A suction assisted ablation device comprising a support surface,having a first and a second face, a plurality of suction elementsdisposed adjacent the support surface on the first face, and at leastone conductive element disposed adjacent the support surface on thefirst face is provided. The first face of the device is placed adjacentan area of tissue. Suction is conducted to the suction elements via thesuction conduit. The tissue is grasped with the suction and ablated. Atleast one fluid outlet may be provided adjacent the support surface andfluid may be released via the fluid outlet. The fluid outlet may belocated within the conductive element. The device may be placed using amaneuvering apparatus. At least one thermocouple element may be placedin communication with at least one suction element and a thermalenvironment of the suction element may be measured using thethermocouple element. The tissue may be ablated until the measurement ofthe thermal environment reaches a given level. A second support surfacehaving a second conductive element disposed adjacent a first face of thesecond support surface may also be provided. The first face of thesecond support surface may be placed in line with the first supportsurface to complete a circuit. The tissue is ablated.

[0013] Another aspect of the invention provides a tissue ablationsystem. The system comprises at least two support surfaces, each supportsurface having a first and a second face, a plurality of suctionelements disposed adjacent the support surface on the first face, atleast one conductive element disposed adjacent the support surface onthe first face, at least one suction conduit operatively connected withthe suction elements, and at least one maneuvering apparatus, such as apull wire assembly. The support surfaces may be disposed consecutivelyto each other in a linear manner along the maneuvering apparatus so thata continuous ablation lesion is achieved. The system may also include afluid delivery system, which may incorporate at least one fluid openingdisposed adjacent the support surface, a fluid conduit, a conductiveelement including fluid openings or a conductive element made of amaterial that releases fluid.

[0014] Another aspect of the invention provides a method of mapping theheart. A suction assisted ablation device comprising a support surface,having a first and a second face, a plurality of suction elementsdisposed adjacent the support surface on the first face, at least oneelectrode disposed adjacent the support surface on the first face and atleast one suction conduit operatively connected with the suctionelements is provided. The first face of the device is placed adjacent anarea of tissue. Suction is conducted to the suction elements via thesuction conduit. The tissue is grasped with the suction. A signal issent through a first electrode. The signal is received through a secondelectrode. The distance is mapped based on the signal from the firstelectrode to the second electrode.

[0015] Another aspect of the invention provides a method of pacing aheart. A suction assisted ablation device comprising a support surface,having a first and a second face, a plurality of suction elementsdisposed adjacent the support surface on the first face, at least oneelectrode disposed adjacent the support surface on the first face and atleast one suction conduit operatively connected with the suctionelements. The first face of the device is placed adjacent an area oftissue. Suction is conducted to the suction elements via the suctionconduit. The tissue is grasped with the suction. Electrical impulses aresent through the electrode at regular interval and the heart is paced tobeat with the impulses.

[0016] Another aspect of the invention provides a method of ablatingtissue. A suction assisted ablation device comprising a support surface,having a first and a second face, a plurality of suction elementsdisposed adjacent the support surface on the first face, at least oneneedle electrode disposed adjacent the support surface on the first faceand at least one suction conduit operatively connected with the suctionelements. The first face of the device is placed adjacent an area oftissue. The tissue is penetrated with the needle electrode. Suction isconducted to the suction elements via the suction conduit. The tissue isgrasped with the suction; and ablated.

[0017] The foregoing, and other, features and advantages of theinvention will become further apparent from the following detaileddescription of the presently preferred embodiments, read in conjunctionwith the accompanying drawings. The detailed description and drawingsare merely illustrative of the invention rather than limiting, the scopeof the invention being defined by the appended claims in equivalencethereof.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1 is a side view of the suction assisted ablation device inaccordance with the present invention shown within a system for ablatingtissue;

[0019]FIG. 2 is a bottom view of one embodiment of the suction assistedablation device of the present invention, showing a first configurationof the suction elements and of the ablation electrodes;

[0020]FIG. 3 is a cross-sectional view of one embodiment of the suctionassisted ablation device of the present invention, showing suctionactivity and ablation pattern at one suction site;

[0021]FIG. 4 is a bottom view of a second embodiment of the suctionassisted ablation device of the present invention, showing a secondconfiguration of the suction elements and of the ablation electrodes;and

[0022]FIG. 5 is a bottom view of another embodiment of the suctionassisted ablation device of the present invention.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

[0023]FIG. 1 shows one embodiment of system 10 for ablating tissue, suchas organic tissue, in accordance with the present invention. Typicallythe tissue to be ablated will be located within the body cavity, such asthe endocardial or epicardial tissue of the heart. Other body organtissue, such as the liver, lungs or kidney, may also be ablated usingthe present invention. Tissue types that may be ablated include skin,muscle or even cancerous tissue or abnormal tissue growth.

[0024] System 10 may include an ablation device 12 that comprises atleast one conductive element 22, such as an electrode, and a connection28 to a power source 30. Ablation device 12 may also include one or moresuction elements 44 and a suction conduit 34 that provides suction froma suction source 20. System 10 also may include a conduit 26 to anirrigation source 40 that provides irrigation fluid to the ablationsite. System 10 may also include temperature-sensitive elements 36,which may have the same power source 30 as the electrodes or may havetheir own power source.

[0025] System 10 may also include an indifferent (non-ablating)electrode 23 which may serve as a return plate for energy transmittedthrough electrode 22. Electrode 23 may be placed elsewhere on thepatient's body other than the ablation site. For example, electrode 23may be placed on the patient's back, thigh or shoulder.

[0026] Ablation device 12 may be any suitable ablation tool such as, forexample, a catheter, an electrocautery device, an electrosurgicaldevice, a suction-assisted ablation tool, an ablation pod, an ablationpaddle, an ablation hemostat or an ablation wire. Ablation device 12 andits components are preferably made of a biocompatible material such asstainless steel, biocompatible epoxy or biocompatible plastic.Preferably, a biocompatible material prompts little allergenic responsefrom the patient's body and is resistant to corrosion from being placedwithin the patient's body. Furthermore, the biocompatible materialpreferably does not cause any additional stress to the patient's body,for example, it does not scrape detrimentally against any elementswithin the surgical cavity. Alternatively, the biocompatibility of amaterial may be enhanced by coating the material with a biocompatiblecoating.

[0027] Preferably, ablation device 12 may be permanently or removablyattached to a maneuvering apparatus for manipulating device 12 onto atissue surface. For example, ablation device 12 may be attached to ahandle 72 such as shown in FIG. 1. Ablation device 12 may also belocated on one or more of the jaws of a hemostat-like device. Ablationdevice 12 may also be used in conjunction with a traditional catheter,for example, in a closed heart ablation procedure. Ablation device 12may also be maneuvered with a leash or pull-wire assembly. Ablationdevice may also be positioned on a pen-like maneuvering apparatus suchas the Sprinkler pen available from Medtronic, Inc. Alternatively anyappropriate flexible, malleable or rigid handle could be used as amaneuvering apparatus. Alternatively, any appropriate endoscopic orthoroscopic-maneuvering apparatus may also be used with device 12.

[0028] Device 12 also preferably includes a connection 28 suitable forconducting energy to device 12, particularly to conductive element 22from a power source.

[0029] The conductive element 22 of ablation device 12 may preferably bean electrode. This electrode 22 may be positioned in any suitable placeon device 12. Preferably electrode 22 is placed near an end of thedevice 12, away from the user, to be more easily manipulated against thetissue 60 to be ablated.

[0030]FIG. 2 shows one embodiment of a device 12 for ablating organictissue in accordance with system 10 of the present invention. Suctionassisted ablation device 12 may comprise at least one face 15 that mayconform to the surface of the target tissue 60. The face 15 may be anyconfiguration that conforms to the surface of the target tissue, such asthe slightly curved or arcuate configuration of FIG. 1. Suction device12 may also include a suction conduit 34 that may be connected to leastone suction port 44 containing a suction opening 54 Suction device mayalso have at least one conductive element 22 disposed adjacent face 15.For example, two conductive elements 22, 42 are shown in FIG. 2.Preferably, the conductive element 22, 42 may be an electrode.Alternatively, suction device 12 may be made of a conductive polymer andmay serve as a conductive element. The distal end of device 12 may bepositioned near the ablation site and the proximal end may be positionedtowards the surgeon.

[0031] Preferably, when face 15 of suction device 12 is positionedagainst the target tissue, face 15 is adapted to conform to the surfaceof the tissue. This may be accomplished by making suction device 12 froma flexible material, such as, for example, a pliable polymer,biocompatible rubber thermoplastic elastomer or PVC. Alternatively,suction device 12 may be made of a more rigid material covered with anelastic over face 15. Suction force being applied through device 12 maycause device 12 to conform more closely to the shape of the targettissue. Device 12 may also be made of a malleable stainless steel orother material that is shapeable but not necessary flexible. Device 12may also be made of a conductive polymer.

[0032] Ablation device 12 may also be permanently or removably attachedto a suction tube 24. Suction conduit 34 may be located within Tube 24.Conduit 34 may communicate suction to the target tissue surface via thesuction openings 54 of suction ports 44 in device 12.

[0033] The suction ports 44 may be arranged three to six ports in a row,although the specific number of ports and their position may vary.Preferably, for a linear lesion to result from the ablation process, theports are arranged linearly. Device 12 may be covered with a coveringduring insertion to prevent blood or tissue from clogging the ports 44,although this is not necessary. Such coverings may include coverings ofbiocompatible material that would cover device 12. Alternatively,coverings may be placed over ports 44, such as, for example, meshcoverings or ribbed coverings.

[0034] Each suction port 44 has a suction opening 54, which may belocated in the center or at a position slightly off-center of suctionport 44. Although the openings 54 are circular in FIG. 2, other shapesmay be used The suction ports 44 may also be any suitable shape. Forexample, in the embodiment of FIG. 2, the ports 44 are rectangular.Additionally, suction openings 54 may be covered with a covering such asdescribed above to prevent blood or tissue from clogging the openings54.

[0035] Preferably, each suction opening 54 has a smaller diameter thanthe area of suction port 44. This creates a high resistance pathwaybetween suction port 44 and suction conduit 34. Because of this, loss ofa tissue-to-port seal in one suction port (and thus loss of fixation ofthe suction port to the tissue) should not cause a precipitous pressuredrop in the remainder of the suction ports.

[0036] Ablation device 12 may be permanently or removably attached to atleast one connection 28 for conveying energy to electrodes 22, 42 frompower source 30. This energy is typically electrical, such asradiofrequency (RF) energy. However, it may also be any appropriate typeof energy such as, for example, microwave or ultrasound energy.Preferably, electrode 22 runs the length of one side of device 12 andelectrode 42 runs the length of the opposite side of device 12.Electrode 22 may be maneuvered into contact with the target tissue toablate the tissue. In the embodiment of FIG. 2, two electrodes are shownin a bipolar arrangement. In such a bipolar arrangement, electrode 42may also be maneuvered into contact with target tissue 60 to ablate thetissue.

[0037] Ablation device 12 may be permanently or removably attached to atleast one fluid conduit 26 for irrigating the ablation site with afluid. Alternatively, ablation site may not be irrigated. Fluid isconveyed to the site via fluid openings 46 which are preferablyintegrated into electrodes 22, 42. However, fluid may be delivered tothe site via a separate irrigation mechanism, such as an irrigation pump(not shown). Moreover, fluid openings 46 may be disposed in anyappropriate manner on device 12.

[0038] Suction ablation device 12 may be colored so that it can beeasily visible against the target tissue. Alternatively, it may be clearto provide less distraction to the surgeon or to provide viewing ofblood or other material being suctioned. Suction tube 24 may be aflexible tube constructed of a soft plastic which could be clear orcolored. Suction ports 44 may be constructed of biocompatible rubber orepoxy, which could be clear or colored.

[0039] Electrodes 22, 42 may be constructed of stainless steel,platinum, other alloys, or a conductive polymer. If device 12 is made ofa more flexible material, electrodes 22, 42 may be made of materialsthat would flex with the device 12. Such flexible electrodes may be, forexample, made in a coil or spring configuration. Flexible electrodes 22,42 may also be made from a gel, such as a hydrogel. Furthermore,electrodes 22, 42 may also be an electrode designed to deliver fluid,such as, for example, a microporous electrode, a “weeping” electrode, oran electrode made of a hydrogel.

[0040] A source 20 for creating suction may be attached to suction tube24 at the proximal end, preferably by a standard connector. This suctionsource 20 may be the standard suction available in the operating roomand may be coupled to the device 12 with a buffer flask (not shown).Suction is provided at a negative pressure of between 200-600 mm Hg with400 mm Hg preferred.

[0041] System 10 may include at least one temperature-sensitive element36. The temperature-sensitive element 36 is positioned to communicatewith at least one of suction ports 44. Preferably, an element 36 ispositioned to communicate with each suction port 44. These elements maybe, for example, thermocouple wires, thermisters or thermochromaticinks. These thermocouple elements allow temperature to be measured. Suchmonitoring of temperature may crucial. Too high a temperature will charthe tissue or cause the blood at the ablation site to coagulate.Preferably, the elements 36 may be adhered within suction ports 44 so asto contact the tissue when it is suctioned into the ports. Thermocoupleelements that may be used are 30 gauge type T thermocouple wire fromDodge Phelps Company. One type of conductive epoxy which may be used toadhere the elements is epoxy no. BA-2902, available from Trecon.

[0042] A separate temperature sensitive element 36 may be adhered ormounted within each suction port 44. Alternatively, a temperaturesensitive element may be incorporated to run through all of the suctionsports 44.

[0043] As ablation occurs, it is sometimes desirable to irrigate theablation site with irrigation fluid, which may be, for example, anysuitable fluid such as saline, an ionic fluid that is conductive oranother conductive fluid. The irrigating fluid may cool the electrode 22of ablation device 12. Irrigated ablation is also known to create deeperlesions that are more likely to be transmural. Transmurality is achievedwhen the full thickness of the target tissue is ablated. The applicationof fluid to an ablation site may also prevent electrodes, particularlymetal electrodes, from contacting the target tissue. Direct contact ofelectrodes to the target tissue may char or burn the tissue, which mayclog the device. Furthermore, continuous fluid flow may keep theablation device surface temperature below the threshold for bloodcoagulation, which may also clog the device Use of irrigating fluid maytherefore reduce the need to remove a clogged ablation device forcleaning or replacement. The presence of an ionic fluid layer betweenelectrode 22 and the tissue to be ablated may also ensure that an ionicfluid layer conforming to the tissue contours is created. In onepreferred embodiment, saline solution is used. Alternatively, otherenergy-conducting liquids, such as Ringer's solution, ionic contrast, oreven blood, may be used. Diagnostic or therapeutic agents, such asLidocaine, CA⁺⁺blockers, or gene therapy agents may also be deliveredbefore, with or after the delivery of the irrigating fluid. Irrigationsource 40 may be any suitable source of irrigation fluid such as, forexample, a standard irrigation pump (not shown). This pump may also beconnected to power source 30 or may have its own source of power.Preferably, device 12 also includes a conduit 26 for deliveringirrigation to the ablation site from irrigation source 40.

[0044] In the embodiment of FIG. 1, fluid openings 46 may be locatedwithin the electrode 22 itself. These openings may be holes machinedinto the electrode 22. These openings may deliver fluid to the ablationsite as described above. Furthermore, electrode 22 may also be anelectrode designed to deliver fluid, such as, for example, a microporouselectrode, a “weeping” electrode, an electrode made of a microporouspolymer or an electrode made of a hydrogel.

[0045] Referring now to FIG. 3, a close-up cross section is shown, takenalong line A-A of FIG. 1. In use, the embodiment of device 12 shown inFIGS. 1 and 2 is placed against target tissue 360 so that when a suctionforce is applied through openings 354, the target tissue is pulled intothe suction port 344. Fluid flows from openings 46 towards the targettissue as indicated by the arrows. Openings 46 are preferably angled atabout 30 degrees. Openings 46 preferably face towards suction ports 344.Ablation may begin at point 300 of the tissue and spread in thedirection indicated by the dotted arrows. If left over time, the entirepiece of tissue suctioned into the ports 344 may be ablated.

[0046] Electrodes 322, 342 are brought to a temperature sufficient toablate the tissue within the ports 44. Thermocouple elements 336 may beused to monitor the temperature and when a given threshold temperatureis reached, the surgeon may end ablation. This configuration of device12 is especially useful because it gives an accurate measurement of thetissue temperature since the tissue 360 is in direct contact with thethermocouple elements 336 located near ports 344. Thus the temperatureof the tissue may be measured by thermocouple elements rather than thetemperature of the electrode 322 being measured. The temperature of thetissue may also be determined based on ablation time.

[0047] The resulting lesion may be transmural. If the tissue is allowedto heat until the elements 336 indicate a temperature that usuallyindicates cell death (such as, for example, 15 seconds at 55°), this mayindicate that all the tissue has reached this temperature. In turn, thismay indicate that the lesion is transmural.

[0048] The ablation resulting from the arrangement of electrodes inFIGS. 2 and 3 is linear. The width of the resulting ablation lesion maybe determined by the space between electrodes 22, 42. The width of theresulting ablation lesion may also be determined by the depth of thesuction port 44 and the amount of the tissue suctioned into port 44 Thedepth of the lesion may be controlled by the depth of the suction port44 and the amount of suction force applied. The depth of the lesion mayalso be determined by the power applied to the conductive element andthe length of ablation time. The lesion resulting from the suction port344 of FIG. 3 will be repeated at each subsequent corresponding suctionport along the length of device 12. It is contemplated that for a longerlesion, a longer pod could be used or a series of pods could be strungtogether. A single pod could also be used to create a longer lesion byablating to create a first lesion and then being moved to create asecond lesion in line with the first lesion.

[0049]FIG. 4 shows another embodiment of the invention shown in FIG. 3.In this embodiment, electrodes 422, 423 are arranged in a unipolararrangement. Electrode 422 is placed on the device 12 while anotherelectrode 423 acts as a ground patch (indifferent, or non-ablatingelectrode) and is placed separately from the device 12. For example,electrode 422 on device 12 could be placed on a surface of the heart.Then corresponding electrode 423, which could be on a separate supportsurface, could be placed on the back of the patient to complete thecircuit. Although the suction ports 444 may be arranged in a linearmanner, ports 444 may be arranged in any other appropriateconfiguration, including for example, in an arcuate or radialarrangement. Although suction openings 454 may be circular, they mayalso be any appropriate shape to deliver suction. The lesions created bythis sort of unipolar arrangement tend to be wider than those created bya bipolar arrangement.

[0050] In the unipolar arrangement of FIG. 4, suction ports 444 are usedto grasp target tissue (not shown) but do not pull the tissue into theports for ablating. Fluid would flow from openings in the electrode 423or in device 12 in the same manner as described above. Ablation wouldoccur in a similar manner to that described above although the device 12remains uniformly on the surface of the target tissue rather thanpulling the tissue into the ports for ablation.

[0051] It is contemplated that the electrodes used in the presentinvention could include any appropriate electrodes for performingablation such as, for example, metal electrodes, braided metalelectrodes or needle electrodes

[0052]FIG. 5 shows another embodiment of the suction ablation device 512of the present invention, in which the conductive element may be aseries of needle electrodes 522. A unipolar arrangement of theelectrodes 522 is shown. Alternatively, the electrodes may be arrangedin a bipolar configuration similar to the arrangement of FIG. 2. In abipolar arrangement, one series of needle electrodes may be arrangeddown the length of one side of the suction ports 544 and another seriesof electrodes 522 arranged down the length of the other side. Needleelectrodes may be used to poke through fatty tissue covering the targettissue. They may then be used to poke into the target tissue. Suctionmay then be applied as described above to hold electrodes in place.Ablation may then occur as described above. Additionally, device 512shows suction conduit 534 which may provide suction to ports 544 andpull wire 572 that serves as a maneuvering apparatus for device 512.

[0053] The device 12 may also be used in electrical mapping functions.For example, electrode 22 may be placed on one area of the heart and anappropriate signal sent through it. Then the electrode 42 may receivethe signal from electrode 22. From the strength of the signal, thedistance of electrode 22 from electrode 42 may be determined. Conductiondelay or block can help determine transmurality of lesions.

[0054] Device 12 may also be used in pacing functions. For example,device 12 may grasp the heart as described above. Then energy may besent through electrodes, 22, 42 at regular intervals. This energy maycause the heart to beat simultaneously to the signals sent throughelectrodes 22, 42. The device 12 may thus pace the heart at anappropriate beating rate, thereby serving as a pacemaker. This may beused, for example, during a surgical procedure when it might benecessary to regulate the heart's beating temporarily.

[0055] It should be appreciated that the embodiments described above areto be considered in all respects only illustrative and not restrictive.The scope of the invention is indicated by the following claims ratherthan by the foregoing description. All changes that come within themeaning and range of equivalents are to be embraced within their scope.

We claim:
 1. A suction assisted ablation device comprising: a supportsurface, having a first and a second face; a plurality of suctionelements disposed adjacent the support surface on the first face; atleast one conductive element disposed adjacent the support surface onthe first face; and at least one suction conduit operatively connectedwith the suction elements.
 2. The device of claim 1 further comprising:a maneuvering apparatus operatively connected with the support surface.3. The device of claim 2 wherein the maneuvering apparatus comprises atleast one pull wire.
 4. The device of claim 1 further comprising: atleast one thermocouple element adjacent the suction elements.
 5. Thedevice of claim 1 further comprising a second separate support surfacewherein a first conductive element is disposed adjacent the firstsupport surface, and a second conductive element is disposed adjacentthe second support surface,
 6. The device of claim 5 wherein the firstsupport surface is positioned to face a first end of an area of tissueand the second support surface is positioned to face a second end of thearea of tissue, thereby completing a circuit.
 7. The device of claim 1wherein the conductive element is a plurality of needle electrodes. 8.The device of claim 1 further comprising: at least one fluid openingdisposed adjacent the support surface.
 9. The device of claim 8 whereinthe fluid opening is located within the conductive element.
 10. Thedevice of claim 7 wherein the conductive element is made of a materialcapable of releasing fluid.
 11. A method of ablating tissue, comprisingproviding a suction assisted ablation device comprising a support:surface, having a first and a second face, a plurality of suctionelements disposed adjacent the support surface on the first face and atleast one conductive element disposed adjacent the support surface onthe first face; placing the first face of the device adjacent an area oftissue; conducting suction to the suction elements via the suctionconduit; grasping the tissue with the suction; and ablating the tissue.12. The method of claim 11, further comprising: providing at least onefluid outlet adjacent the support surface; and releasing fluid via thefluid outlet.
 13. The method of claim 11 wherein the fluid outlet islocated within the conductive element.
 14. The method of claim 10wherein the device is placed using a maneuvering apparatus.
 15. Themethod of claim 11, further comprising: providing at least onethermocouple element in communication with at least one suction element;and measuring a thermal environment of the suction element using thethermocouple element.
 16. The method of claim 15, further comprising:ablating the tissue until the measurement of the thermal environmentreaches a given level.
 17. The method of claim 10 further comprising:providing a second support surface having a second conductive elementdisposed adjacent a first face of the second support surface; placingthe first face of the first support surface adjacent an area of tissue;conducting suction to the suction elements via the suction conduit;grasping the tissue with the suction; placing the first face of thesecond support surface in line with the first support surface tocomplete a circuit; and ablating the tissue.
 18. A tissue ablationsystem comprising: at least two support surfaces, each support surfacehaving a first and a second face; a plurality of suction elementsdisposed adjacent the support surface on the first face; at least oneconductive element disposed adjacent the support surface on the firstface; at least one suction conduit operatively connected with thesuction elements; and at least one maneuvering apparatus along which thesupport surfaces are disposed.
 19. The system of claim 18 wherein thesupport surfaces are disposed consecutively to each other in a linearmanner along the maneuvering apparatus so that a continuous ablationlesion is achieved.
 20. The system of claim 18 wherein the maneuveringapparatus is a pull wire assembly.
 21. The system of claim 18 furthercomprising: a fluid delivery system operatively attached to the supportsurface.
 22. The device of claim 21 wherein the conductive element ismade of a material capable of releasing fluid.
 23. The system of claim18 further comprising: at least one fluid opening disposed adjacent thesupport surface; a fluid conduit operatively attached to the fluidopening to release fluid from the opening.
 24. The device of claim 23wherein the fluid opening is located within the conductive element. 25.A method of mapping the heart, comprising: providing a suction assistedablation device comprising a support surface, having a first and asecond face, a plurality of suction elements disposed adjacent thesupport surface on the first face, at least one electrode disposedadjacent the support surface on the first face and at least one suctionconduit operatively connected with the suction elements; placing thefirst face of the device adjacent an area of tissue; conducting suctionto the suction elements via the suction conduit; grasping the tissuewith the suction; sending a signal through a first electrode; receivingthe signal through a second electrode; and mapping the distance based onthe signal from the first electrode to the second electrode.
 26. Amethod of pacing a heart, comprising: providing a suction assistedablation device comprising a support surface, having a first and asecond face, a plurality of suction elements disposed adjacent thesupport surface on the first face, at least one electrode disposedadjacent the support surface on the first face and at least one suctionconduit operatively connected with the suction elements; placing thefirst face of the device adjacent an area of tissue; conducting suctionto the suction elements via the suction conduit; grasping the tissuewith the suction; sending electrical impulses through the electrode atregular intervals; and pacing the heart to beat with the impulses.
 27. Amethod of ablating tissue, comprising: providing a suction assistedablation device comprising a support surface, having a first and asecond face, a plurality of suction elements disposed adjacent thesupport surface on the first face, at least one needle electrodedisposed adjacent the support surface on the first face and at least onesuction conduit operatively connected with the suction elements; placingthe first face of the device adjacent an area of tissue; penetrating thetissue with the needle electrode; conducting suction to the suctionelements via the suction conduit; grasping the tissue with the suction;and ablating the tissue.